Railroad freight cars typically include an elongated car body supported toward opposite ends by a pair of wheeled trucks. Each wheeled truck includes a bolster laterally extending between two side frames with a wheel and axle assembly arranged to front and rear sides of the bolster. Each railcar also has a brake system operably associated therewith. A conventional brake system includes a brake beam assembly associated with each wheel and axle assembly and which is connected to brake rigging on the car. Each brake beam assembly is supported between the truck side frames to allow it to be operated into and out of braking positions in relation to the respective wheel and axle assembly.
A typical brake beam assembly primarily includes compression and tension members fastened to each other at their ends where a brake head is located and separated at the middle by a strut or fulcrum. It has been found beneficial for the brake beam assembly to maintain both a degree of camber in the compression member and a degree or level of tension in the tension member. Each brake head on the brake beam assembly is preferably configured to have a brake shoe connected to and carried thereby. Moreover, an end-guide extends from each end of the brake beam assembly and is supported for sliding movements within cast slots or guides provided on an inner face of each side frame of the wheeled truck.
The brake beam assemblies on the railcar are operated in simultaneous relation by a power source from a brake cylinder or a hand brake and, through leverage, transmit and deliver braking forces to the brake shoes at the wheels of each wheel and axle assembly. On a typical railcar, the brake rigging, including a brake push rod, transmits force, caused by the push of air entering the brake cylinder or by the pull of the hand brake, to the brake shoes.
The brake rigging on the railcar, used to transmit and deliver braking forces to the braking shoes of each wheel assembly, comprises a multitude of linkages including various levers, rods and pins. For example, brake levers are used throughout the brake rigging on each car to transmit as well as increase or decrease the braking force on each wheel and axle assembly. The distance between various holes or openings on the brake levers determine the force transmitted to or between the various levers. Besides transferring force, the linkages of the brake rigging are also used to change the direction of force. The levers used in a brake rigging are named from the various conditions and positions they serve. For example, there are body levers, such as the cylinder lever and fulcrum lever, and there are truck levers, such as a live truck lever and a dead truck lever associated with each wheeled truck on the railcar.
The strut or fulcrum of each brake beam assembly pivotally supports either a live or dead truck lever. Besides being pivotally supported by the brake beam assembly strut, one end of the live truck lever is articulately connected to a longitudinally elongated top rod whose opposite end is connected to the cylinder lever of the railcar brake rigging. As is known, and besides being pivotally supported by the strut of the other brake beam assembly on the wheeled truck, the dead truck lever is articulately connected, intermediate the strut and the free end thereof, to the live truck lever by a truck lever connection. The free end of the dead truck lever is typically fulcrumed to the truck bolster or car body by a guide used to adjust the brakes. As known, a center rod serves to articulately connect the cylinder lever and fulcrum lever through a slack adjuster of the brake rigging. Suffice it to say, there are multiple articulate connections between the various body levers, truck levers, and operating rods comprising the brake rigging on a railcar.
During use, a railcar can travel tens of thousands of miles between locations and over railbeds, some of which can be in significant disrepair. Accordingly, and although most component parts of the brake beam assembly are made from steel, it is not unusual for one or more of the brake beam assembly components or parts on one or more of the brake beam assemblies on the railcar to become cut, worn, twisted, dented, cracked or broken under the relative high forces imparted thereto. Of course, severe wear, cracking, denting, twisting or breaking of a brake beam assembly component part can adversely affect railcar braking performance and, thus, result in condemnation of the brake beam. As will be appreciated, parts of or, in severe cases, sometimes the entire brake beam assembly may be missing from the railcar.
Accordingly, railroad freight cars are routinely inspected. Part of the inspection process involves an analysis of each railcar brake beam assembly on the railcar. Heretofore, when a particular railroad freight car is identified as having a brake beam assembly requiring repair or replacement, the freight car requiring such repair must be initially separated from the remaining cars in the train consist and, then, moved to a facility where such repairs can be affected. Separating that particular freight car from the remaining cars in the train consist, coupled with moving that railcar, along with scheduling of the required repairs can take hours if not days. Of course, during this time, the railcar requiring such repair must be and is removed from service.
Only after a suitable repair facility has been identified and becomes available, can replacement of the damaged brake beam assembly be affected. The heretofore known method for replacing a damaged railcar brake beam assembly is a time consuming process. One of the first steps in such process involves disconnecting those linkages of the brake rigging from the damaged brake beam assembly. That is, the damaged brake beam assembly needs to be disconnected from the truck levers, operating rods and other linkages of the brake rigging as well as from the other brake beam assembly mounted on the respective railcar truck.
That end of the railcar body supported by the wheeled truck having the defective brake beam assembly needs to be sufficiently elevated or raised to allow the wheeled truck to be rolled from under the railcar body to a predetermined location. As will be appreciated by those skilled in the art, an empty railroad freight car can weigh tens of thousands of pounds. A hopper car filled with a commodity can weigh 50 or more tons. Accordingly, lifting of the railcar body involves using special hydraulic jacks connected to a suitable hydraulic pump or other suitable hydraulic pressure source for raising and, thus, separating the wheeled truck from the railcar body. As will be appreciated, suitable hydraulic conduits or hoses need to extend between the hydraulic jacks and the hydraulic pump. Moreover, such hydraulic jacks need to be positioned over a concrete pad suitably constructed to withstand the weight of the freight car being lifted by the jacks. To promote the distribution of the freight car weight over a broadened or increased area, suitable planks of wood or other suitable material are typically placed under each hydraulic jack.
After the railcar body is raised and separated therefrom, the wheeled truck having the defective or condemned brake beam assembly thereon is rolled from beneath and away from the railcar body. Thereafter, a specially designed truck hoist is positioned adjacent to the railcar truck such that the ends of the side frames, adjacent to the defective brake beam assembly, can be conjointly and pivotally elevated to allow the wheel and axle assembly, arranged adjacent to the condemned brake truss assembly, to be removed from between the side frames. As is known, a typical railcar truck further includes a wheel bearing adapter positioned between each side frame and each end of the wheel and axle assembly. In an effort to avoid damage to the wheel bearing adapters when the side frames are elevated, steps must be taken to temporarily maintain each adapter in positional relation relative to the respective side frame of the wheeled truck to inhibit inadvertent separation of the adapter from the elevated side frame.
After pivotally raising the side frames ends of the relevant wheel and axle assembly and removing the wheel and axle assembly from between the side frames is there sufficient access to permit removal of the defective brake beam assembly. With the wheel and axle assembly so removed, replacing the condemned brake beam assembly further involves displacing or prying the side frames of the respective railcar truck in opposed lateral directions relative to each other. Notably, only after prying the side frames laterally apart from each other is the distance between the side frames sufficiently increased to finally allow the free ends of the defective brake beam assembly to be removed from within the cast slots or guides on the side frames of the railcar truck. Some newer designs of freight car wheeled trucks require a special tool for laterally spreading the side frames in opposed lateral directions to increase the lateral spacing therebetween. In either case, and as will be appreciated, great care must be exercised in laterally spreading the side frames apart from each other so as to limit damage to the bearings mounting the other wheel and axle assembly on the wheeled truck.
After having finally removed the damaged/defective brake beam assembly, a new brake beam assembly can be positioned for installation into operable combination with the railcar truck. That is, and with the side frames of the truck remaining pried laterally apart to substantially increase the distance between the cast slots or guides on the side frames, the free ends of the new brake beam are aligned with their respective cast slots or guides on the side frames and the side frames are again brought back to their conventional position. As such, the free ends of the brake beam are entrapped within the cast slots or guides on the side frames for guided reciprocatory movements. With some newer wheeled railcar truck designs, considerable effort can be required to return the side frames such that a standard lateral spacing is provided therebetween.
After a replacement brake beam is installed into operable combination with the side frames, the wheel and axle assembly is returned beneath the raised ends of the side frames. The side frames are lowered onto the wheel and axle assembly and those devices used to temporarily maintain each wheel bearing adapter in fixed positional relation relative to a respective side frame can be removed. After having replaced the brake beam assembly, and after returning the side frames to their original position, and after having arranged the wheel and axle assembly in operable combination with the side frames, the reassembled railcar truck can be again rolled beneath the raised end of the railcar body. The jacks or lifts are operated to lower the railcar body onto the railcar truck having the replacement brake beam associated therewith. Next, the jacks, their hydraulic hoses, and wood planking can be removed from the area adjacent to the railcar body. After the brake rigging linkages are again connected to the brake beam, replacement of the brake beam assembly is finally complete. Thereafter, the railcar having the replacement brake beam mounted thereon needs to be joined to another train consist and is again routed to its original destination.
The American Association of Railroads (the “AAR”) has established a recommended time frame for completing replacement of a damaged brake beam assembly. According to the AAR, replacement of a brake beam should be accomplished within 1.44 hours. It should be appreciated, however, the 1.44 hours allocated by the AAR for replacement of a brake beam assembly neither considers the valuable time lost in separating the railcar with the damaged brake beam from the remaining cars in the train consist, nor the time lost in scheduling a repair facility to accomplish replacement of the brake beam assembly, nor the time lost in having to move the car with the damaged brake beam to the repair facility for replacement of the brake beam assembly. Additionally, the time allocated by the AAR does not consider the time lost in joining the repaired car to a train consist directed toward the original destination of the repaired car. Moreover, the overhead costs of the special equipment required to lift the railcar body from the wheeled truck, along with that special equipment used to elevate the ends of the railcar side frames from operable association with the relevant wheel and axle assemblies, and related special equipment used to affect replacement of the brake beam assembly needs to be considered.
Thus, there is a continuing need and desire for a method for replacing a brake beam assembly on a railroad freight car which is less time consuming and, overall, less costly than heretofore known and long accepted procedures.